1. Field of the Invention
This invention relates to improvements in valves and more particularly, but not by way of limitation, to a ball valve having removable sealing means and removable valve seat means.
2. Description of the Prior Art
Ball valves are in widespread usage today for providing control of fluid flo through flow lines, and the usual ball valve comprises a housing having inlet and outlet ports providing a fluid passageway through the valve whereby the fluid may flow in either direction through the housing. A rotatable closure member is disposed within the housing between the ports and is usually in the form of a ball member having a central bore extending diametrically therethrough whereby in one orientation of the ball member the bore is in alignment with the ports for providing an open position for the valve, and in another orientation of the ball member communication between the ports is precluded for providing a closed position for the valve. In some instances, the closure member is of a substantially U-shaped cross sectional configuration with the outer periphery thereof being substantially semi-spherical for engagement with suitable valve seat means in the closed position of the valve in both the open end and closed position of the closure member, with the open portion of the "U" being disposed in alignment with the ports in the open position of the valve for permitting the passage of fluid through the housing regardless of the direction of flow of the fluid. The closure member is usually operably connected with a rotatable valve stem which extends through the valve housing substantially perpendicularly with respect to the direction of fluid flow through the valve, and which is normally provided with an external operator means for transmitting rotation to the valve stem and closure member. As the closure member rotates between the open and closed positions therefor, the outer periphery thereof is in constant engagement with the valve seat and sealing means, and considerable friction and wear is generated on the seat and seal, and as a result it may be frequently necessary to replace both the valve seat and the sealing means. In the presently available valves of this type, the replacement of the valve seat and sealing means usually presents a problem and is time consuming and expensive in that a considerable amount of disassembly is often necessary to perform the replacement operation.